coolant temperature TOYOTA TUNDRA 2020 Owners Manual (in English)

1062. Instrument cluster
Fuel gauge
Displays the quantity of fuel remaining in the tank.
Shift position and shift range display
Displays the selected shift position or selected shift range. ( P. 225)
Odometer and trip meter display
Displays the following items.
Odometer:
Displays the total distance the vehicle has been driven.
Trip meter:
Displays the distance the vehicle has been driven since the met er was last
reset. Trip meters A and B can be used to record and display different dis-
tances independently.
Multi-information display
Presents the driver with a variety of driving-related data. ( P. 111)
Displays warning messages in case of a malfunction. ( P. 491)
Engine coolant temperature gauge
Displays the engine coolant temperature.
Instrument panel light control button
7
8
9
10
11
12

1092. Instrument cluster
2
Instrument cluster
NOTICE
■To prevent damage to the engine and its components
● Do not let the indicator needle of the tachometer enter the red zone, which
indicates the maximum engine speed.
● The engine may be overheating if the engine coolant temperature gauge is
in the red zone (H). In this case, immediately stop the vehicle in a safe
place, and check the engine after it has cooled completely. ( P. 5 2 7 )
■ Vo l t m e t e r
When the voltmeter indicates 19 V or higher or 9 V or lower whi le the engine
is running, there may be a battery or charging system malfunction. Have the
vehicle inspected at your Toyota dealer.
■ Engine oil pressure gauge
When the value of the engine oil pressure gauge drops while the engine is
running, stop the vehicle in a safe place immediately and check the amount
of engine oil. ( P. 416)
When the oil pressure drops even though the engine oil amount h as not
decreased, or if the oil pressure does not increase when engine oil is
added, contact your Toyota dealer, as there may be a problem wi th the lubri-
cation system.

2104-1. Before driving
●Avoid sudden braking as you may skid, resulting in the trailer jack-
knifing and a loss of vehicle control. This is especially true on wet or
slippery surfaces.
● Avoid jerky starts or sudden acceleration.
● Avoid jerky steering and sharp turns, and slow down before maki ng
a turn.
● Note that when making a turn, the trailer wheels will be closer than
the vehicle wheels to the inside of the turn. Compensate by mak ing
a wider than normal turning radius.
● Slow down before making a turn, in crosswinds, on wet or slippe ry
surfaces, etc.
Increasing vehicle speed can destabilize the trailer.
● Take care when passing other vehicles. Passing requires consider-
able distance. After passing a vehicle, do not forget the lengt h of
your trailer, and be sure you have plenty of room before changi ng
lanes.
● To maintain engine braking efficiency and charging system perfo r-
mance when using engine braking, do not use the transmission in
D.
Transmission shift ra nge position must be in 4 in the S mode.
● Instability happens more frequently when descending steep or lo ng
downhill grades. Before descending, slow down and downshift. Do
not make sudden downshifts while descending steep or long down-
hill grades.
● Avoid holding the brake pedal down too long or applying the bra kes
too frequently. This could cause the brakes to overheat and result in
reduced braking efficiency.
● Due to the added load of the trailer, your vehicle’s engine may over-
heat on hot days (at temperatures over 85°F [30°C]) when drivin g
up a long or steep grade. If the engine coolant temperature gau ge
indicates overheating, immediately turn off the air conditionin g (if in
use), pull your vehicle off the road and stop in a safe spot.
(  P. 527)

4136-3. Do-it-yourself maintenance
6
Maintenance and care
WARNING
The engine compartment contains many mechanisms and fluids that may
move suddenly, become hot, or become electrically energized. To avoid death
or serious injury, observe the following precautions.
■When working on the engine compartment
● Keep hands, clothing and tools away from the moving fan and eng ine
drive belt.
● Be careful not to touch the engine, radiator, exhaust manifold, etc., right
after driving as they may be hot. Oil and other fluids may also be hot.
● Do not leave anything that may burn easily, such as paper and r ags, in the
engine compartment.
● Do not smoke, cause sparks or expose an open flame to fuel or t he bat-
tery. Fuel and battery fumes are flammable.
● Be extremely cautious when working on the battery. It contains poisonous
and corrosive sulfuric acid.
■ When working near the electric cooling fan or radiator grille
Be sure the engine switch is off.
With the engine switch in ON, the electric cooling fan may auto matically
start to run if the air conditioning is on and/or the coolant temperature is
high. ( P. 420)
■ Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc.,
from getting in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear
due to dirt in the air.

4196-3. Do-it-yourself maintenance
6
Maintenance and care
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene
glycol based non-silicate, non-amine, non-nitrite, and non-bora te coolant with
long-life hybrid organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -31 F [-35 C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deion-
ized water. (Minimum temperature: -44 F [-42 C])
For more details about coolant, contact your Toyota dealer.
■ If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine coolant reservoir ca p, drain cock
and water pump.
If you cannot find a leak, have your Toyota dealer test the cap and check for
leaks in the cooling system.
WARNING
■ When the engine is hot
Do not remove the radiator cap.( P. 529)
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.
NOTICE
■ When adding coolant
Coolant is neither plain water nor straight antifreeze. The cor rect mixture of
water and antifreeze must be used to provide proper lubrication , corrosion
protection and cooling. Be sure to read the antifreeze or coolant label.
■ If you spill coolant
Be sure to wash it off with water to prevent it from damaging p arts or paint.

481
7
When trouble arises
7-2. Steps to take in an emergency
If you think something is wrong
●Fluid leaks un der the vehicle.
(Water dripping from the air conditioning a fter use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temperature gauge needle continually points high er
than normal.
● Voltmeter continually points higher or lower than normal
● Engine oil pressure gauge cont inually points lower than normal
● Automatic transmission fluid temperature warning message is dis -
played
● Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the engine
● Engine misses, stumbli ng or running roughly
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one s ide when driving on a level road
● Loss of brake effectiveness, spongy feeling, pedal almost touch es
the floor
If you notice any of the followi ng symptoms, your vehicle proba -
bly needs adjustment or repair. Contact your Toyota dealer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms

4927-2. Steps to take in an emergency
(Flashes)
Indicates that the engine was stopped while driv-
ing.A buzzer also sounds.
 Stop the vehicle in a safe place such as the
shoulder of a road.
Indicates that the engine coolant temperature is
too high
A buzzer also sounds.
 Immediately stop the vehicle in a safe place
and contact your Toyota dealer.
Indicates a malfunction in the automatic transmis-
sion system
A buzzer also sounds.
 Have the vehicle inspected by your Toyota
dealer immediately.
(If equipped)
Indicates a malfunction in the intuitive parking
assist
The malfunctioning assist-sensor is flashing.
 Have the vehicle inspected by your Toyota
dealer immediately.
(If equipped)
Indicates a malfunction in the Blind Spot Monitor
A buzzer also sounds.
 Have the vehicle inspected by your Toyota
dealer immediately.
Indicates that one or more of the doors or the
hood is not fully closed
The system also indicates which doors are not
fully closed.
If the vehicle reaches a speed of 3 mph
(5 km/h), flashes and a buzzer
sounds to indicate that the door(s) are not
yet fully closed.
 Make sure that all the doors and the hood
are closed.
Warning messageDetails/Actions
Engine Stopped

Stop In a Safe Place
Engine Coolant
Temp High
Stop in a Safe Place
See Owner’s Manual
CHECK
TRANSMISSION
SYSTEM
Parking Assist Malfunction
Blind Spot Monitor Malfunction
Visit Your Dealer

527
7
When trouble arises
7-2. Steps to take in an emergency
If your vehicle overheats
●The needle of the engine coolant temperature gauge ( P. 1 0 5 )
enters the red zone or a loss of engine power is experienced. ( For
example, the vehicle speed does not increase.)
● “ENGINE COOLANT OVERTEMP” is shown on the multi-informa-
tion display.
● Steam comes out f rom under the hood.
Stop the vehicle in a safe place and turn off the air condition ing sys-
tem, and then stop the engine.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the engine has cooled
down sufficiently, inspect the
hoses and radiator core (radia-
tor) for any leaks. Radiator
Cooling fan
If a large amount of coolant leaks,
immediately contact your Toyota
dealer.
The following may indicate that your vehicle is overheating:
Correction procedures
1
2
3
1
2

5297-2. Steps to take in an emergency
7
When trouble arises
WARNING
■When inspecting under th e hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
● If steam is seen coming from under the hood, do not open the ho od until
the steam has subsided. The engine compartment may be very hot.
● Keep hands and clothing away from the fans, etc., while the engine is run-
ning.
● Do not loosen the radiator cap and the coolant reservoir cap wh ile the
engine and radiator are hot.
High temperature steam or coolant could spray out.
NOTICE
■ When adding engine coolant
Add coolant slowly after the engine has cooled down sufficientl y. Adding
cool coolant to a hot engine too quickly can cause damage to th e engine.
■ To prevent damage to the cooling system
Observe the following precautions:
● Avoid contaminating the coolant with foreign matter (such as sa nd or dust,
etc.).
● Do not use any coolant additives.

599Alphabetical index
If the warning message is displayed......................... 491
If you have a flat tire ............. 504
If you lose your keys ............. 123
If you think something
is wrong .............................. 481
If your vehicle becomes
stuck ................................... 530
If your vehicle has to be stopped in an emergency ... 473
If your vehicle needs to be towed ......................... 476
If your vehicle overheats ....... 527
Emergency flashers ................ 472
Engine “ACC” position ...................... 217
Compartment ........................ 415
Engine switch........................ 217
Hood ..................................... 414
How to start the engine ......... 217
Identification number ............ 539
If the engine will not start ...... 519
Ignition switch
(engine switch) ................... 217
Immobilizer system ................. 85
Overheating .......................... 527
Engine coolant ......................... 418 Capacity ................................ 543
Checking ............................... 418
Preparing and checking before winter....................... 331
Engine coolant temperature gauge...................................... 105
Engine immobilizer system ...... 85
Engine oil ................................. 416
Capacity ................................ 541
Checking ............................... 416
Preparing and checking before winter....................... 331
Engine oil maintenance
data ......................................... 407
Engine switch (ignition switch)..................... 217 Engine switch light
(ignition switch light) ............ 357
Event data recorder (EDR)........ 11
Flat tire ..................................... 504
Floor mats .................................. 30
Fluid
Automatic transmission ........ 544
Brake .................................... 545
Washer ................................. 425
Fog lights ................................. 244 Replacing light bulbs ............ 464
Switch ................................... 244
Wattage ................................ 548
Foot well light .......................... 357
Four-wheel drive system ........ 315
Front passenger occupant classification system .............. 53
Front personal lights............... 358
Front seats ............................... 147 Adjustment............................ 147
Cleaning ............................... 403
Correct driving posture ........... 32
Driving position memory ....... 152
Head restraints ..................... 157
Power easy access system .......... ...................... 152
Seat heaters ......................... 354
Seat position memory ........... 152
Seat ventilators ..................... 354
Front side marker lights Light switch ........................... 234
Replacing light bulbs ............ 462
Wattage ................................ 548
Front turn signal lights Replacing light bulbs ............ 461
Turn signal lever ................... 232
Wattage ................................ 548
F